Battery life of wireless devices is one of the major concerns for wireless network operators and one of the main parameters describing user experience with new wireless devices.
Wireless communication devices are increasingly becoming capable of providing a wide-range of functions such computing capabilities, Internet access, electronic mail, text messaging, GPS mapping, digital photographic capability, an audio/MP3 player, video gaming capabilities, video broadcast reception capabilities and the like. However, many of these features and functions are power intensive applications that are characterized by high rates of battery power consumption.
On top of these, being connected to a WLAN has also an impact on the battery consumption of theses devices. 802.11 MAC WLAN protocol defines only to mode of operation in which the mobile device can operate i.e. Active Mode (AM) or Power Saving Mode (Power Saving Mode). In current implementations, when in sleep state, the wireless device wakes up in regular time intervals to read system information which is broadcasted by the network. This is because the mobile device is unable to determine the destination of the packet until it receives it. Further to this, the mobile host also has to perform a handover at every Access Point cell boundary in order to maintain association with the Access Point.